I need to start thinking about my next vehicle, any thoughts

[jaybet]

I know Toyota has had a lot of 'splainin' to do lately, but we have a 2005 Toyota 4Runner that is an absolute tank. Needs a little fix now and then but it's always running and it's got good 4 wheel drive. I spun off into a front end crash with a tree once and it's still going.

[bafsu92]

here is the deal with AWD.  when you have 1 wheel that is spining at a diffrent rate then all the others, it can and will wear out parts in the AWD system.  It can also mess with some of the traction control systems in AWD( subbys and GM systems the most)  remember small changes in hieght, can make huge diffrence in thier circumference

Lets just say your tires are 24" tall and have 1/8" of wear.  that 1/8" is really  1/4"

so a new tire will be 24 1/4" tall.  

now your old tires have a circumfrence of  ~75.36"  the new tire has is ~  76.15 for a diffrence of .79"

now that does not sound like much, but there are 63360 inchs per mile.  now divide that by your circufrences.

for every mile you travel your old tires will be rotating 840.76 times.  the new tire will be rotating  832.04

but your awd is having to slip 8 rotations per mile.

There is not a car manufactor that makes a AWD that does not recomend you replace all the tires at once, large tire vendors also have policys about it as they don't want the liabilty if it does F up your AWD.



you are free to do what you like.

4wd systems are diffrent as they the spilt the power between 2 axles, awd spilt the power between all 4 wheels.

Sounds somewhat logical however I too would've made the air pressure argument. I wasn't saying either of us was right or wrong, just that I've never heard that. I could see where it might make a difference on the same axle, maybe but really don't see where even a full inch of height would make a difference front to rear. I've probably put a million miles on 4X4's in my life time and never had any type of axle, gear or transfer case failure. I've changed gears by choice and have run every type of limited slip or locker configuration on the market. Maybe the fact that the bulk of my vehicles have had at least 33" or taller tires makes a difference. A 1/2" isn't really that much of a difference when it comes to that size tire, about 2# of pressure can lower a 1/2" on a 33" tire. Unlike the bulk of people who own 4X4 vehicles I use mine pretty regularly, at least once or twice a week now and at many times in my life daily. I have an onboard ARB compressor since  I regularly adjust tire pressures for off road driving.

As a side note I just read through the entire tire section in my owners manual and I can't find anywhere in it that says or even recommends tires be changed only by 4's. There are lots of things about the AWD/4WD system but nothing about the tires related to it. I've got 85k on this particular one and had another that I had over 300K on with no issues either so I guess I'm not screwing up too badly with my tire management.